Speedtimer is the name Seiko gives its chronographs, and it goes back a long way. Seiko moved onto the international sports timing stage in the 1960s with a new generation of high-precision equipment, and in 1969 put the name on a wristwatch: the Seiko Speedtimer, driven by Calibre 6139 — the world's first automatic chronograph with a column wheel and vertical clutch. The Seiko Prospex HBJ005P1 carries that line into Seiko's 145th anniversary.

This reference is a solar chronograph. Calibre V192 runs on light alone — no battery to replace — and holds roughly six months of charge once full. The anniversary colour is Edo purple, set against black sub-dials and a black-and-purple aluminium bezel carrying a tachymetre scale. The chronograph times to 1/5th of a second over 60 minutes, there is a power reserve indicator and a date, and the case back is engraved LIMITED EDITION on a run of 8,000 pieces.